Cushion floor

ABSTRACT

The flooring structure is composed of three layers. The upper layer is a wear layer surface which may have decorative design or configuration. The lower layer is a cushion of foam backing which is generally resilient. Between the upper and lower layers there is deposited a layer which is used to distribute the load applied on the upper layer to a wire surface area of the lower layer. The load distributing structure may be a plurality of interconnected plates, a thin unitary sheet structure or a sheet structure divided into a plurality of interconnected plates.

Aug. 15, 1972 SENSENK; ETAL 3,684,630 cUsHIoN' FLOOR Filed March 9. 1970"Unnnnnnjfl, 7f '[////V/ 2 o o D a o O O o o a INVENTOR DARRYLL-SENSENlG ROBERT LSHAUB, JR-

ATTORNEY Iliad States Patent O 3,684,630 CUSHION FLOOR Darryl L.Sensenig, Columbia, and Robert I. Shaub, Jr.,

Willow Street, Pa, assignors to Armstrong Cork Company, Lancaster, Pa.

Filed Mar. 9, 1970, Ser. No. 17,479 Int. Cl. B32b 3/18 U.S. Cl. 161-36 2Claims ABSTRACT OF THE DISCLOSURE The flooring structure is composed ofthree layers. The upper layer is a wear layer surface which may have adecorative design or configuration. The lower layer is a cushion or foambacking which is generally resilient. Between the upper and lower layersthere is deposited a layer which is used to distribute the load appliedon the upper layer to a wide surface area of the lower layer. The loaddistributing structure may be a plurality of interconnected plates, athin unitary sheet structure or a sheet structure divided into aplurality of interconnected plates.

BACKGROUND OF THE INVENTION Field of the invention The invention hereinis directed to a floor covering structure and, more particularly, to acushion fioor covering with a built-in load distributing means.

Description of the prior art US. Pat. No. 2,569,709 discloses a flexiblewood floor covering which is composed of a unitary sheet structure witha plurality of grooves converting the sheet structure into a pluralityof interconnected plate elements. This structure is used to provide acovering on an irregularly contoured floor surface or to provide a floorsurface which will not warp or bulge upon taking up moisture. This floorstructure is not resilient in the sense that a load applied to the uppersurface is distributed to a large area of the underlying surface.

US. Pat. No. 3,001,902 is directed to a tile structure which has aplurality of plate-like elements fastened to the back surface of thewear layer. Again, this floor is made flexible so that it may be appliedto uneven surfaces. Likewise, here there is no indication of a loaddistribution feature.

Finally, U.S. Reissue Patent No. 26,239 discloses a floor structurewhich utilizes pads under the floor covering to provide a resiliency tothe upper floor structure. The above structure is basically a resilientsupport for a con ventional wood flooring laid over a concrete base.Here there is no teaching of a load distribution from a small uppersurface area to a large underlying resilient surface area.

SUMMARY OF THE INVENTION The invention deals with the construction of abacking layer for the wear surface of a floor covering so that therewill be provided improved under-foot cushioning comfort along with verygreat resistance to damage to the upper floor surface. The feature ofthe construction which provides for the limited damage to the uppersurface while still permitting a cushioning effect is the positioning ofa load distributing structure between the upper wear layer surface andthe underlying cushioning surface. The load distributing structure isgenerally a rigid material. This rigid material is normally cut,embossed or routed to make geometrical shapes or plates. The cut orrouted areas do not out completely through the rigid material, and thereis provided a structure comparable to a plurality of rigid platesinterconnected by resilient hinges. Of

ice

course, this structure could be made by merely placing a plurality ofrigid plates on a continuous sheet, which functions as a resilient hingebetween the individual plates.

This particular load distributing structure is placed between the upperwear layer structure and a relatively thick cushioning layer. Aconcentrated force applied to the upper surface of the wear layer isdistributed by the rigid plate structure to a wide area of theunderlying cushion material. With the interconnected plate structure,the plates will not bend appreciably, but there will be a bendingbetween two plates at the groove area between the two plates. Thisfeature thus helps to distribute the load over a large area of theunderlying cushion material. It has been found that a load distributingstructure along with a low compression modulus lower layer material willstill permit the desired cushioning comfort and yet be extremelyresistant to puncture plus recover immediately from long-term staticload or other types of compression.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a side view of an embodimentof the structure herein with the wear surface in a nonstressed state;and I FIG. II is a showing of the structure of FIG. I in a stressedcondition.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. I, there isshown the three-layer structure of the invention herein. The floorstructure 2 has three layers. The lower layer 4 is a conventionalfoamtype material such as that utilized in Patent No. 2,961,029. Theupper layer 6 is a conventional Wear layer surface such as that shown inthe above-mentioned patent. This particular wear layer surface may beprovided with a decorative design or a decorative surface configuration.The primary function of the upper layer is to provide a toughwear-resistant coating to the overall floor covering 2. The layer 4 ismeant to provide a resilient backing to the overall flooring 2 so thatthe [flooring will provide an under-foot cushioning comfort due to thefact that it gives to some degree under the feet of a person walkingthereacross. With lloor structures having just the upper wear layer andthe resilient undersurface, high heel, spiked shoe heels, chair legs,table legs, etc., tend to apply a very large force in a concentratedarea. This force is transmitted by the wear layer to the resilientmaterial directly under the wear layer. There is very little tendencyfor the surface wear layer to distribute the load over a wide area ofthe cushion material and thus diminish the depth to which the wear layeris depressed. The deeper the wear layer is depressed the greater is thetendency to rupture the wear layer and to crush the underlying cushionmaterial. It is normal practice when tables and chairs are placed onthis type of flooring to place load distributing plates or discs underthe table or chair leg and on top of the wear layer. This thus tends todistribute the load of the table or chair over a larger area than wouldnormally be utilized if the leg of the table or chair were permitted torest directly on the wear layer.

The above load distribution feature of the unsightly appearing loaddistributing plates or discs is accomplished through the utilization ofthe load distribution layer 8 of the invention herein. This layer 8 isdeposited between the wear layer 6 and the cushion layer 4 so that aconcentrated force placed upon the wear layer 6 is distributed over asubstantially large area of the cushion material 4. Generally, a rigidmaterial is utilized for the layer 8, and this material has a thicknessless than 0.050 and has an elastic modulus greater than 5x10p.s.i./inch/inch.

The cushion layer has a low compression modulus of 2 to 20p.s.i./inch/inch with a good short and long-term recovery. Since therigidity of the rigid material is a function of its elastic modulus andthickness, variations of the above two factors may be used as long asthey give the same resultant as the above structure.

In one preferred embodiment, the load distribution layer is made from a30-mil steel plate which has a series of grooves 9 cut therein in a gridpattern to form 3" squares. The grooves do not extend completely throughthe steel; and, therefore, the steel plate-like structures areinterconnected by hinge elements 10. The cushion layer is a low modulusurethane foam of 6 p.s.i./inch/inch. The grooved rigid material isplaced on the cushion layer with the opening of the grooves facing down.The wear layer is placed on the nongrooved side of the metal layer 8.When the load is applied with the openings of the grooves face down, theplates themselves will not bend appreciably, but there will be bendingat the grooves as shown in FIG. II. Since these hinge plates will notbend appreciably, loads will not be concentrated at one spot, but willbe distributed over adjacent plates.

It is possible that the load distributing layer 8 could be made from aplurality of separate plastic plates which are individually adhered to athin resilient material; and, therefore, this resilient material wouldform the hinges between the plates. Also, the plates could beindividually embedded in the foam backing 6 and the foam function as theindividual plate hinges. It is even conceivable that a single sheetstructure could be used as the load distributing layer 8. Certainplastic-type materials could Well function in this manner and therebyprovide a load distributing feature for a load placed on the Wear layerwhile at the same time give a cushioning effect.

What is claimed is:

1. In a floor covering having a thick backing layer of resilientmaterial, a thin upper layer of a Wear resistant material, theimprovement in the combination therewith comprising a means betweenthese two layers for distributing a load applied to a small surface areaof the upper layer to a large surface area of the resilient backinglayer, said load distributing means is a plurality of rigid, plate-likeelements connected together by a resilient hinge-like structure.

2. The floor covering of claim 1 wherein the lower layer has an elasticmodulus in the range of 2 to 20 p.s.i./inch/ inch while the loaddistributing means has an elastic modulus greater than 5x10p.s.i./inch/inch with a thickness of less-than 0.050".

References Cited UNITED STATES PATENTS 2,556,884 6/1951 Muller 161-392,621,712 12/1952 Millar et a1. 161--117 3,425,889 2/1969 Willits1611-17 3,445,320 5/1969 Boivin '16183 2,768,924 10/1956 Wright l61-1613,393,109 7/1968 Durst 16136 3,516,898 6/1970 Cook 16136 FOREIGN PATENTS801,433 8/1936 France 156-211 MORRIS SUSSMAN, Primary Examiner US. Cl.X.R.

